The present invention relates to an image forming apparatus, an image forming system and a computer program of the same.
There has been well known the book-binding technology for creating a booklet in which a bunch of recording papers to be contents of the booklet (hereinafter, the term of the abovementioned “recording papers” is referred to as “main content sheets”) is covered by a cover sheet in such a manner that the main content sheets are enveloped by the cover sheet while one side, upper and lower sides of the bunch of the main content sheets are made to be open. In addition, there has been also well known the image forming apparatus that produces such the cover sheet on which a front cover image, a back cover image and a lining cover image are formed so as to provide the cover sheet mentioned in the above.
For instance, Patent Document 1 (Tokkai 2000-332987, Japanese Non-Examined Patent Publication) set forth the method for determining the reading width of the lining cover document by setting the width of the lining cover when reading the lining cover document, and reading the lining cover document.
The width of lining cover should be determined, based on the thickness of the bunch of the main content sheets. However, if the thickness of the bunch of the main content sheets is different from the value presumed in advance, it is necessary to change the width of the lining cover to new one.
According to the Patent Document 1, in the case mentioned in the above, the setting value of the width of the lining cover should be changed. However, since the reading width of the lining cover document becomes different from that established in advance due to the width change mentioned in the above, the lining cover image would be formed at a position shifted from the center of the lining cover sheet in its width direction when reading the lining cover document, which was initially prepared so as to position the image at the center of the lining cover sheet in its width direction, as it is. Accordingly, it has been a problem that it should be necessary to generate a new lining cover document in which the center of the image coincided with that of the lining cover sheet in its width direction based on the changed width of the lining cover sheet.